Endoscopic surgical instruments have been developed for use in endoscopic surgical procedures. The endoscopic surgical instruments, although rugged, must be properly packaged for sterilization and shipment and handling in order to prevent damage to the instruments. Many endoscopic surgical instruments are packaged in conventional thermoformed plastic blister packages. Thermoformed blister packages are well known and are manufactured using conventional thermoforming processes wherein a sheet of polymer is typically heated and drawn by a vacuum into a mold. The thermoformed blister packages are typically designed to have a number of cavities which conform to the contours of particular surgical instruments. The surgical instruments are placed within these cavities and the cavities serve to both retain and cushion the instruments during sterilization, shipping and handling. Many thermoformed blister packages consist of a relatively rigid, thermoformed polymer lower tray and a flexible polymer cover which is typically gas permeable. The cover may also be a thermoformed polymer cover and may have cavities. A flange typically extends about the outer periphery of the blister tray to which the cover is sealed. The sealing may be accomplished by a number of conventional processes including ultrasonic welding, heat sealing and the use of various adhesives and bonding agents.
For shipment, handling and storage, it is necessary to place the blister packaged instrument into an outer package. The outer package serves several functions. It protects the blister package from inadvertent cuts, punctures and tears thereby preventing the compromising of the sterility of the instrument. The package also serves to add a degree of additional protection to the blister package in the event of accidental drops or impacts.
It is especially critical in packaging a sealed, blister packaged, sterile instrument to protect the seal of the blister package. Although most thermoformed blister trays are relatively rigid, they are still capable of flexing during normal shipping, handling and storage. This flexing is known to cause the flanges to twist and bend. Such movements can potentially cause the cover seal to delaminate in those areas where the twisting or torsional forces and/or bending are extreme or where the seal may be weak. Delamination will typically result in the compromise of the sterility of the interior of the package and its contents. This can be a major problem since most disposable medical instruments and medical devices cannot be re-sterilized in the field. In order to prevent this type of flexing, it is necessary to somehow support the flanges of the blister package when it is inserted into an outer package and to stiffen the outer package. Present approaches utilize massive amounts of polymeric foams, such as polyurethane foam, to cushion and protect the packages and support the flanges. There are various disadvantages associated with polymeric foam. One disadvantage is that in order for the foam to be effective, a relatively large quantity of the foam is required thereby increasing the size of an outer box into which the blister packed instrument is packaged. Another disadvantage of the polymeric foams is the fact that they are difficult to dispose of and recycle. Yet another disadvantage is that larger outer boxes are required for a foam packed blister package resulting in additional shelf space in a hospital supply storage area being taken up.
Therefore, it is an object of the present invention to provide an outer package for a thermoformed blister packaged endoscopic instrument which supports the flanges of the blister packages without the need for a polymeric foam outer cushion.
It is a further object of the present invention to provide a package which supports the flange of a blister package thereby minimizing twisting and flexing and bending of the flange of the blister package and decreasing the possibility of a seal delaminating.
It is yet a further object of the present invention to provide a package for a blister package which has improved stiffness.